Hinge for micro-mirror devices
View Patent ↗An improved hinge for a micro-mirror device composed of a conductive doped semiconductor and immune to plastic deformation at typical to extreme temperatures. The hinge is directly connected to the micro-mirror device and facilitates the manufacturing of an optically flat micro-mirror. This eliminates Fraunhofer diffraction due to recesses on the reflective surface of the micro-mirror. In addition, the hinge is hidden from incoming light thus improving contrast and fill-factor.
1. A micro-mirror device comprising:
a doped semiconductor hinge comprising a post supported on and extended from a substrate having a cantilever formed as a thin-narrow-plate extended from said post wherein said cantilever further having a mirror supporting platform as a separate cantilever segment for supporting a micromirror thereon; and
said post supported on and extended from said substrate is further formed as a hollow post comprising side-walls with said cantilever extending vertically from one of said side-walls as a vertical cantilever for connecting to said mirror supporting platform as a horizontal mirror supporting platform as said separate cantilever segment.
2. The micromirror device of claim 1 wherein:
said doped semiconductor hinge is composed of a material selected from a group of semiconductors consisting of elemental semiconductors, III–V compound semiconductors, II–VI compound semiconductors, IV compound semiconductors, and alloy semiconductors.
3. The micromirror device of claim 1 wherein:
said doped semiconductor hinge is formed by employing a semiconductor formation process selected from a group of semiconductor formation processes consisting of deposition by solid-phase epitaxy, deposition by vapor-phase epitaxy, deposition by liquid-phase epitaxy, deposition by molecular-beam epitaxy, thin film deposition by physical evaporation, thin film deposition by electron-beam evaporation, thin film deposition by filament evaporation, thin film deposition by flash evaporation, thin film deposition by sputtering, thin film deposition by CVD, bulk substrate wafer slice from single crystal ingot, SOS substrate, and SOI substrate.
4. The micromirror device of claim 1 wherein:
said doped semiconductor hinge is doped with an doping impurity selected from a group doping impurities consisting of group III elements, group IV elements, group V elements, and group VII elements is introduced into said semiconductor.
5. The micromirror device of claim 4 wherein:
said doped semiconductor hinge is doped with said doping impurity by employing a doping process selected from a group of doping processes consisting of ion-implantation, constant-source diffusion, limited-source diffusion, two-step diffusion, substrate autodoping, substrate out-diffusion, in situ deposition, and in situ crystallization.
6. The micromirror device of claim 5 wherein:
said doped semiconductor hinge is doped with said doping impurity selected from a group of doping impurities consisting of solid doping impurities, liquid doping impurities, vapor doping impurities, and gas doping impurities.
7. The micromirror device of claim 6 wherein:
said doped semiconductor hinge is doped with said doping impurity formed from a source of doping impurity selected from a group of doping impurity sources consisting of PSG, BSG, BPSG, AsSG, SbSG, Arsine, diborane, phosphine, boron trioxide, trimethylborate, boron nitride, boron tribromide, phosphorus pentoxide, ammonium monophosphate, ammonium diphosphate, phosphorus oxychloride, arsenic trioxide, antimony trioxide, antimony pentachloride, silane, dichlorosilane, and stabine.
8. The micromirror device of claim 7 wherein:
said doped semiconductor hinge is annealed by a process selected from a group of annealing processes consisting of furnace annealing, laser annealing, rapid thermal annealing, lamp annealing, and electrical conduction heating.
9. The micromirror device of claim 1 wherein:
said micro-mirror is assembled by a process selected from a group of processes consisting of self-assembly, adhesive bonding, silicon fusion bonding, anodic bonding, and monolithic fabrication.
10. The micromirror device of claim 1 wherein:
said doped semiconductor hinge is composed of a material selected from a group of semiconductors consisting of amorphous silicon, polycrystalline silicon, and single crystal silicon.
11. The micromirror device of claim 1 further comprising:
a second post for supporting a second micromirror with said second post supported on and extended from said substrate is further formed as a hollow post comprising side-walls with said cantilever extending from one of said side-walls.
12. The micromirror device of claim 1 wherein:
said post extending above a top surface of said substrate with a vertical height above said top surface.
13. The micromirror device of claim 1 wherein:
said post extending to a top surface of said substrate with a zero vertical height above said top surface.